To measure, by radioimmunoassay, estrone sulfate, dehydroepiandrosterone sulfate, and androsterone sulfate in the plasma of at least one hundred patients per group, either with diagnosed breast cancer or diagnosed benign breast tumors or apparently normal controls in order to assess adrenal activity in postmenopausal women and adrenal and ovarian activity in young women, with or without breast cancer or benign breast tumor, and use the values obtained as possible diagnostic and/or prognostic parameters in breast cancer.